TY - JOUR
T1 - Evaluation of the North American Land Data Assimilation System over the southern Great Plains during the warm season
AU - Robock, Alan
AU - Luo, Lifeng
AU - Wood, Eric F.
AU - Wen, Fenghua
AU - Mitchell, Kenneth E.
AU - Houser, Paul R.
AU - Schaake, John C.
AU - Lohmann, Dag
AU - Cosgrove, Brian A.
AU - Sheffield, Justin
AU - Duan, Qingyun
AU - Higgins, R. Wayne
AU - Pinker, Rachel T.
AU - Tarpley, J. Dan
AU - Basara, Jeffery B.
AU - Crawford, Kenneth C.
PY - 2003/11/27
Y1 - 2003/11/27
N2 - North American Land Data Assimilation System (NLDAS) land surface models have been run for a retrospective period forced by atmospheric observations from the Eta analysis and actual precipitation and downward solar radiation to calculate land hydrology. We evaluated these simulations using in situ observations over the southern Great Plains for the periods of May-September of 1998 and 1999 by comparing the model outputs with surface latent, sensible, and ground heat fluxes at 24 Atmospheric Radiation Measurement/Cloud and Radiation Testbed stations and with soil temperature and soil moisture observations at 72 Oklahoma Mesonet stations. The standard NLDAS models do a fairly good job but with differences in the surface energy partition and in soil moisture between models and observations and among models during the summer, while they agree quite well on the soil temperature simulations. To investigate why, we performed a series of experiments accounting for differences between model-specified soil types and vegetation and those observed at the stations, and differences in model treatment of different soil types, vegetation properties, canopy resistance, soil column depth, rooting depth, root density, snow-free albedo, infiltration, aerodynamic resistance, and soil thermal diffusivity. The diagnosis and model enhancements demonstrate how the models can be improved so that they can be used in actual data assimilation mode.
AB - North American Land Data Assimilation System (NLDAS) land surface models have been run for a retrospective period forced by atmospheric observations from the Eta analysis and actual precipitation and downward solar radiation to calculate land hydrology. We evaluated these simulations using in situ observations over the southern Great Plains for the periods of May-September of 1998 and 1999 by comparing the model outputs with surface latent, sensible, and ground heat fluxes at 24 Atmospheric Radiation Measurement/Cloud and Radiation Testbed stations and with soil temperature and soil moisture observations at 72 Oklahoma Mesonet stations. The standard NLDAS models do a fairly good job but with differences in the surface energy partition and in soil moisture between models and observations and among models during the summer, while they agree quite well on the soil temperature simulations. To investigate why, we performed a series of experiments accounting for differences between model-specified soil types and vegetation and those observed at the stations, and differences in model treatment of different soil types, vegetation properties, canopy resistance, soil column depth, rooting depth, root density, snow-free albedo, infiltration, aerodynamic resistance, and soil thermal diffusivity. The diagnosis and model enhancements demonstrate how the models can be improved so that they can be used in actual data assimilation mode.
KW - Data assimilation
KW - Soil moisture
KW - Surface fluxes
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U2 - 10.1029/2002jd003245
DO - 10.1029/2002jd003245
M3 - Article
AN - SCOPUS:1342330990
SN - 0148-0227
VL - 108
SP - GCP 7-1 - GCP 7-21
JO - Journal of Geophysical Research: Atmospheres
JF - Journal of Geophysical Research: Atmospheres
IS - 22
ER -